Bobbin head



Feb. 4, 1941.

H. W. MACK -BOBBIN HEAD Filed April 19, 1939 Patente Feb. 4, 1941 I BOBBHN an Henry W. Mack, Allentown, Pa, assignor to The Allentown Bobbin Works, lira, Allentown, Pa, a corporation of Pennsylvania.

Application April 19, 1939, Serial No. 268,699

4 Claims.

The invention relates to bobbin heads, such as, for example, are used for bobbins carrying silk and artificial silk fiber during'the processes of throwing and conditioning.

One purpose of the invention is to reduce warpage in a bobbin head of synthetic resin, such as Bakelite. v

A further purpose is to reduce brittleness in a bobbin head so as to protect against chipping and other breakage.

A further purpose is to make the entire crosssection of the bobbin head more nearly homogeneous and to bring the center of gravity and the center about. which expansion and contraction take place into the center of the head.

A further purpose is to secure strength and freedom from brittleness by the distribution within each bobbin thickness of many layers of synthetic resin having a fabric base and to avoid the otherwise objectionable effect of this in roughening the edge and in warpage by reinforcing and adjacently supporting the textile fiber by interspersed layers of synthetic resin having a paper base.

A further purpose is to use'a fabric base synthetic resin characterized by fine textile fibers and to support these fibers closely by paper base synthetic resin. I

A further purpose is to prevent chipping by supporting all paper base synthetic resin at the perimeter by intervening closely associated layers of fabric synthetic resin.

A further purpose is to improve the quality of textile fiber (fabric) base synthetic resin' layers in the bobbin head by reducingthe thickness of the fibers, increasing the extent of their impregnation and immediately supporting the fibers by intervening layers having paper bases.

' Further purposes will appear in the specification and in the claims.

I have preferred to illustrate one form only of the invention, selecting a form which has proved to be practical, effective, highly durable and inexpensive and which at the same time well illustrates the principles involved.

In the drawing Figure l is a fragmentary elevation partly in section of a bobbin head embodying my invention.

Figure 2 is an end elevation of the bobbin head of Figure 1.

Figure 3 is a side elevation of a bobbin with heads such as are seen in the other figures.

In the drawing similar numerals indicate like parts.

My bobbin head is useful for all the purposes for which such heads are used, with silk as well as with artificial fibers such as rayon, all of which will be referred to herein as silk. Likewise the bobbin heads are used on bobbins for a variety of purposes including throwing and conditioning, all of which purposes will be treated hereafter merely as conditioning because normally conditioning is the last operation before the thread is transferred to shipping bobbins, cones, etc.

Bobbin heads for bobbins intended to hold silk during conditioning and to be engaged by silk during the transfer from the bobbin must have smooth enough inner surfaces and peripheral surfaces where engaged by the silk not to fray the silk and must have strength enough to stand the mechanical strains involved. They must not warp objectionably and should not be brittle enough to chip or otherwise break from blows which inevitably they will receive in ordinary use.

Two general types of synthetic resin, herein, for convenience, called resin have been used in bobbin heads. The one type is made from a textile fiber base known as of fabric base. Successive layers of such fabric base resin outwith a rough surface or will roughen with use. The other type is a paper base resin which when used in any considerable thickness has been; subject to chipping and breakage.

Attempt has been made to use heads made up of the fabric base resin but they have not been smooth enough to present satisfactory guidir g perimetral surfaces. In an effort to get away from this roughness of surface, heads also have been made having the inner surface of the heads and half or more of the thickness of paper base resin and the rest of the thickness of successive layers of fabric ba e resin. These have ofiered, very smooth perimbtral guiding surfaces and have had'ample strength as distinguished from brittleness but have zones of different materials in the thickness of the head. They have also chipped and'have broken.

I have aimed to secure the benefits of both forms while avoiding their objectionable features, using fabric base resin for the end layer for one end and desirably for both ends of the head, providing a number of layers of fabric base resin between the faces and avoiding the objectionable roughness previously associated with the use of fabric base resin by making the intervening, layers of fabric. base thin and interspersing be tween them thin layers of paper base resin, preferably thicker than the fabric. base resin layers,

for the purpose of immediately supporting the fiber surfaces of the fabric base resin by these layers of paper base resin.

In addition to the benefit from interspersing preferably single layers of fabric base resin by thin layers of paper base resin I gain the further benefit of more complete impregnation of the individual thin fibers than of thicker fibers.

These can be completely impregnated with a molasses-like impregnating syrup under conditions of heat and high pressure. Complete impregnation of the fibers of 6 oz. duck for example has been effected attemperatures of approximately 300 F. and by pressure of 1500 lbs. per square inch.

The stiffness and support given to the head by the layers of paper base resin prevent the laminated form of head shown from substantial warpage and'the immediate support of the fibers of the fabric base resin by the paper base resin at the pointof cutting prevents these fibers from tearing or fraying and permits clean, smooth cutting of the periphery, leaving a surface which has proved to be quite satisfactory as a guiding suring l2.

face for the silk. At the same time the paper base resin layers are protected by the fabric base resin.

In the illustration; one form of a complete .bobbin as now used is shown for the purpose of locating the parts. It comprises a; barrel 6, with heads I and"8. In use the silk engages the face 9 of the head 8 and approximately half I!) of .the rounded periphery II of the head 8.

The head is secured to the barrel by any suitable means, conventionally shown as by fasten- The bobbin is driven by means not shown. The speed varies in different installations, up to the orderof ten thousandrevolutions.

thickness of the heads may vary widely.

With a head thickness approximating and a ratio of of fabric base resin to 70% paper base resin and 9 layers of fabric base resin to 8 layers of paper base resin I have had very excellent results. The inside fabric base layers were of duck weighing a little more than 6 ozs. to the yard and the outer layers slightly lighter.

I have used successfully a smaller number oflayers of slightly heavier duck for the base and the same thickness of head and ratio of fabric base resin (compressed) to paper base resin (compressed). I have. also used linen (duck) base resin successfully in such heads having a weight of duck of 4 ozs. to the yard.

The ratio of 30% fabric base to 70% paper base resin in the heads is not a hard and fast ratio but is determined largely by economical considerations and by the fact that this ratio gives good support of the fibers of the fabric base resin by the paper base resin at the perimeter without increasing the masses of paper base resin in the layers to a point where they will,

chip or break.

With tne weights of duck discussed high pressure and high temperature impregnation from a relatively thick solution of synthetic resin into the fine threads of the light weight duck secures much more nearly complete impregnation with these resins than would otherwise be possible so that the very threads themselves are more firmly supported against bending and fraying during the cutting operation at the perimeter than would otherwise be the case.

The result of the fineness of thread, the facing with fabric base resin upon both faces and the interspersing of alternate thin spacing and supporting layers throughout the thickness along with the impregnation gives a body to the bobbin which cuts clean and which is smooth to the silk fiber. My bobbin head is also equally strong and equally smooth upon either face and the heads may be used with either face out.

As will be seen the cross-section of the head is nearly homogeneous, the layers in their compressed form are quite thin and the center of gravity lies in the center of the length of the head.

Since all of the longitudinal cross-section of the head is made up of the alternating thin layers of impregnated textile fiber base and paper base resin and all of it is equally supported against fraying or tearing or pulling of the textile fiber where it is out. all of the rim as cut is equally free from objectionable fiber at the surfaces and against any projecting fiber which should engage and fray or tear the silk.

It will be evident that the stratificationof the textile fiber base and paper base layers 'makes the cross-section very much stronger throughout than would be a paper base resin alone and avoids the warpage due to different coefficients of expansion of the sharply different paper base resin and fabric base resin found in the prior art; and that the interspersion of the thin layers of paper base resin between the textile fiber base resin layers better support these textile fiber base layers than is the case when the entire cross section or any considerable bulk of it is made of fabric base resin alone as in one of the prior art bobbin heads noted.

In view of my invention and disclosure variationsand modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art, to obtain all or part of the benefits of my invention without copying the structure shown, and I, therefore, claim all in so far as they fall within the reasonable spirit and scope of my invention.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

'1. A textile bobbin having a head comprising a plurality of alternate layers of fabric base synthetic resin and paper base synthetic resin and having a layer of fabric basesynthetic resin on the inside face of the head. 7

2. A textile bobbin having a head made up of outer and inner faces of fabric base synthetic resin adjacent paper base synthetic resin layers and having at the perimeter successive alternate layers of fabric base synthetic resin and paper base synthetic resin each supporting the other and continuing from the inside of the head past the middle of the thickness of the head.

3. A textile bobbin having a head out at the perimeter and consisting of a plurality of thin layers of fabric base synthetic resin interspersedbetween layers of paper base synthetic resin, the fabric base resin bei'ng impregnated by heat and by pressure greatly in excess of atmospheric pres-' sure and the fabric base synthetic resin forming a plurality of alternate layers of fabric base and paper base synthetic resins with the fabric base .resin forming the inner face of the head, the fabric of the fabric base layers of approximately six ounces per square yard weight and impregnated with a thick varnish solution and the 5 thickness of the fabric base layers being approx imately half that of the paper base layers.

HENRY W. MACK. 

